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Employee and Retiree Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Thrift Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Company matching contribution (percent)	100.00%
Employee's maximum contribution matched by Company (percent)	6.00%
Profit sharing percentage 1	5.00%
Profit sharing percentage 2	7.00%
Profit sharing percentage 3	9.00%
Profit sharing contributions	$ 9,216	$ 8,879	$ 4,567
Profit Sharing Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Profit sharing contributions	$ 1,848	$ 1,848	$ 1,861

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- Definition

Defined Contribution Plan, Profit Sharing Percentage 1

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Defined Contribution Plan, Profit Sharing Percentage 2

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Defined Contribution Plan, Profit Sharing Percentage 3

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

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Percentage employer matches of the employee's percentage contribution matched.

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- Definition

Amount of payroll tax expense, compensation, postemployment and benefit-related expenses not elsewhere specified in the taxonomy (such as health plan, profit sharing, incentives, tuition reimbursement, other fringe benefits and perquisites) incurred in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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